Merge pull request #82701 from glessard/rdar154776967-generalize-expectNil

[stdlibUnittest] generalize `expectNil(_:)`

Author: glessard

stdlib/private/StdlibUnittest/StdlibUnittest.swift

@@ -739,18 +739,38 @@ public func expectDoesNotThrow(_ test: () throws -> Void,
   }
 }
 
-public func expectNil<T>(_ value: T?,
+public func expectNil<T>(
+  _ value: T?,
   _ message: @autoclosure () -> String = "",
   stackTrace: SourceLocStack = SourceLocStack(),
   showFrame: Bool = true,
-  file: String = #file, line: UInt = #line) {
+  file: String = #file, line: UInt = #line
+) {
   if value != nil {
     expectationFailure(
-      "expected optional to be nil\nactual: \"\(value!)\"", trace: message(),
+      "expected optional to be nil\nactual: \"\(value!)\"",
+      trace: message(),
       stackTrace: stackTrace.pushIf(showFrame, file: file, line: line))
   }
 }
 
+@_lifetime(copy value)
+public func expectNil<T: ~Copyable & ~Escapable>(
+  _ value: borrowing T?,
+  _ message: @autoclosure () -> String = "",
+  stackTrace: SourceLocStack = SourceLocStack(),
+  showFrame: Bool = true,
+  file: String = #file, line: UInt = #line
+) {
+  if value != nil {
+    expectationFailure(
+      "expected optional to be nil",
+      trace: message(),
+      stackTrace: stackTrace.pushIf(showFrame, file: file, line: line)
+    )
+  }
+}
+
 @discardableResult
 @_lifetime(copy value)
 public func expectNotNil<T: ~Copyable & ~Escapable>(

test/stdlib/OptionalGeneralizations.swift

@@ -1,8 +1,7 @@
-// RUN: %target-run-simple-swift(-enable-experimental-feature NonescapableTypes -enable-experimental-feature LifetimeDependence)
+// RUN: %target-run-simple-swift(-enable-experimental-feature Lifetimes)
 // REQUIRES: executable_test
 // REQUIRES: reflection
-// REQUIRES: swift_feature_NonescapableTypes
-// REQUIRES: swift_feature_LifetimeDependence
+// REQUIRES: swift_feature_Lifetimes
 
 import StdlibUnittest
 import Swift
@@ -99,7 +98,7 @@ suite.test("expectNotNil()") {
   _ = expectNotNil(opt1(NoncopyableStruct()))
   _ = expectNotNil(opt1(RegularClass()))
 #if $NonescapableTypes
-  @lifetime(copy t)
+  @_lifetime(copy t)
   func opt2<T: ~Copyable & ~Escapable>(_ t: consuming T) -> T? { t }
 
   let ne = NonescapableStruct()
@@ -110,5 +109,25 @@ suite.test("expectNotNil()") {
 
   let nent = NonescapableNontrivialStruct()
   _ = expectNotNil(opt2(nent))
-#endif
+#endif // $NonescapableTypes
+}
+
+suite.test("expectNil()") {
+  func opt1<T: ~Copyable>(_ t: consuming T) -> T? { nil }
+  expectNil(opt1(TrivialStruct()))
+  expectNil(opt1(NoncopyableStruct()))
+  expectNil(opt1(RegularClass()))
+#if $NonescapableTypes
+  @_lifetime(copy t)
+  func opt2<T: ~Copyable & ~Escapable>(_ t: consuming T) -> T? { nil }
+
+  let ne = NonescapableStruct()
+  expectNil(opt2(ne))
+
+  let ncne = NoncopyableNonescapableStruct()
+  expectNil(opt2(ncne))
+
+  let nent = NonescapableNontrivialStruct()
+  expectNil(opt2(nent))
+#endif // $NonescapableTypes
 }